The University of Arizona Health Sciences Center and the Arizona Comprehensive Cancer Center propose to establish the Southwest Animal Imaging Resource (SWAIR). The purpose of the SWAIR is to provide the cancer research community access to state-of-the-art in vivo imaging based on magnetic resonance (MR), single photon emission computed tomography (SPECT) and optical coherence tomography (OCT). The integrated program will also provide common access to essential cores for veterinary anesthesia and computing/electrical engineering. The major purpose of the SWAIR will be to provide state-of-the-art imaging access to the base grants. Eight cancer-related research programs form the original cohort of base grants. These represent diverse aspects of cancer research, from basic cellular and molecular mechanisms, to diagnosis, to monitoring and improving therapeutic response. The program will support continuing research to improve the application of the imaging modalities to cancer biology in vivo. MR research will continue to improve methods for spectral imaging (MRSI), high resolution morphometry, motion-insensitive diffusion imaging, pH imaging, and analyses of Gadolinium-enhanced dynamic contrast. These techniques will be applied and developed on newly upgraded 4.7 and 9.4 Tesla instruments. SPECT research will involve construction of a state-of-the-art high-resolution FASTSPECT system, which will be dedicated to animal imaging. Research will focus on improved detectors, readout electronics, and system characterization. The latter is essential for optimizing the spatial resolution of the SPECT system. In the OCT program, a dedicated instrument will be constructed and applied non-invasively to image skin lesions in experimental animals. Research will continue to improve the applicability of this relatively new technology to the diagnosis and serial monitoring of epidermal and epithelial lesions in vivo. Research will also be conducted in the veterinary anesthesia core to continue to improve anesthesia formulations that do not interfere with the physiology being measured. This is an important issue since these modern imaging techniques monitor functional properties of tumors, which can be perturbed in the anesthetized state. The electrical/computing core will help with the construction and maintenance of the imaging instruments. It will also provide support the general computing resources of the entire program.